Graduate School of Frontier Biosciences, Osaka University

Japanese

Lamin B receptor recognizes specific modifications of histone H4 in heterochromatin formation.

Journal J Biol Chem 287, 42654-42663 (2012)
Authors Yasuhiro Hirano (1), Kohji Hizume (2), Hiroshi Kimura (1), Kunio Takeyasu (3), Tokuko Haraguchi (4) and Yasushi Hiraoka (1)
  1. Graduate School of Frontier Biosciences, Osaka University
  2. Division of Microbial Genetics, National Institute of Genetics
  3. Graduate School of Biostudies, Kyoto University
  4. Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology
Title Lamin B receptor recognizes specific modifications of histone H4 in heterochromatin formation.
PubMed 23100253
Laboratory Nuclear Dynamics Group 〈Prof. Hiraoka〉
Abstract Inner nuclear membrane (INM) proteins provide a structural framework for chromatin, modulating transcription beneath the nuclear envelope (NE). Lamin B receptor (LBR) is a classical INM protein that associates with heterochromatin, and its mutations are known to cause Pelger-Huët anomaly in humans. However, the mechanisms by which LBR organizes heterochromatin remain to be elucidated. Here, we show that LBR represses transcription by binding to chromatin regions that are marked by specific histone modifications. The tudor domain (residues 1-62) of LBR primarily recognizes histone H4 lysine 20 dimethylation and is essential for chromatin compaction, while the whole nucleoplasmic region (residues 1-211) is required for transcriptional repression. We propose a model in which the nucleoplasmic domain of LBR tethers epigenetically-marked chromatin to the NE and transcriptional repressors are loaded onto the chromatin through their interaction with LBR.